On one level, it wouldn't take much work - Fluid Operations have written some very good code. Porting it should be relatively straight forward. However, there are two things that would cause me not to include support for VMFS in DiscUtils.

#1 - The code is licensed under GPL. I'm not an expert on how and when code under different licenses can be combined and whether a C# port of some Java code constitutes a derivative work. Inclusion of GPL code within DiscUtils could place the the whole
of DiscUtils under the remit of the GPL. I've chosen to license DiscUtils under the MIT license, which is less restrictive on how the source code can be used.

#2 - Irrespective of the licensing concerns, Fluid Operations have clearly invested a lot of time and effort in understanding the VMFS file system, and offer the code under alternative licenses for a fee. I wouldn't be comfortable taking their hard work
and making it available under an MIT license without first gaining their blessing.

I should be clear, that Fluid Operations choice of GPL license is, in my eyes, a fine choice by them. I'm no zealot over licensing - they've invested a lot of time and effort in what they've done, and it's absolutely their right to license their work
in a way that satisfies their business model.